Net Carrying Values of Debt Securities (Detail) (USD $) In Thousands	Aug. 31, 2011
Available-for-Sale Securities, amortized cost
Less than one year	$ 3,659
One year through five years	14,426
Six years through ten years	5,728
After ten years	3,392
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	27,205
Available-for-Sale Securities, fair value
Less than one year	3,656
One year through five years	14,906
Six years through ten years	6,223
After ten years	3,827
Available-for-sale Securities, Debt Securities, Total	$ 28,612

This item represents debt securities, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are expected to mature after five years and through ten years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

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